NAME DESCRIPTION Incompatible Changes Core Enhancements
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Perl version 5.12.4 documentation - perl5113delta NAME perl5113delta - what is new for perl v5.11.3 DESCRIPTION This document describes differences between the 5.11.2 release andthe 5.11.3 release. If you are upgrading from an earlier release such as 5.11.1, first readthe perl5112delta, which describes differences between 5.11.1 and5.11.2 Incompatible Changes Filehandles are blessed directly into IO::Handle, as FileHandle is merely a wrapper around IO::Handle. The previous behaviour was to bless Filehandles into FileHandle(an empty proxy class) if it was loaded into memory and otherwiseto bless them into IO::Handle. Core Enhancements Unicode version Perl is shipped with the latest Unicode version, 5.2, dated October 2009. See http://www.unicode.org/versions/Unicode5.2.0 for details about this releaseof Unicode. See perlunicode for instructions on installing and usingolder versions of Unicode. Unicode properties Perl can now handle every Unicode character property. A new pod, perluniprops, lists all available non-Unihan character properties. Bydefault the Unihan properties and certain others (deprecated and Unicodeinternal-only ones) are not exposed. See below for more details onthese; there is also a section in the pod listing them, and why they arenot exposed. Perl now fully supports the Unicode compound-style of using = and :in writing regular expressions: \p{property=value} and \p{property:value} (both of which mean the same thing). Perl now fully supports the Unicode loose matching rules for textbetween the braces in \p{...} constructs. In addition, Perl also allowsunderscores between digits of numbers. All the Unicode-defined synonyms for properties and property values arenow accepted. qr/\X/, which matches a Unicode logical character, has been expanded to workbetter with various Asian languages. It now is defined as an extendedgrapheme cluster. (See http://www.unicode.org/reports/tr29/).Anything matched previously that made sense will continue to be matched. Butin addition: \X will now not break apart a CR LF sequence. \X will now match a sequence including the ZWJ and ZWNJ characters. \X will now always match at least one character, including an initial mark.Marks generally come after a base character, but it is possible in Unicode tohave them in isolation, and \X will now handle that case, for example at thebeginning of a line or after a ZWSP. And this is the part where \Xdoesn't match the things that it used to that don't make sense. Formerly, for example, you could have the nonsensical case of an accented LF. \X will now match a (Korean) Hangul syllable sequence, and the Thai and Laoexception cases. Otherwise, this change should be transparent for the non-affected languages. \p{...} matches using the Canonical_Combining_Class property werecompletely broken in previous Perls. This is now fixed. In previous Perls, the Unicode Decomposition_Type=Compat property and aPerl extension had http://perldoc.perl.org Page 1 Perl version 5.12.4 documentation - perl5113delta the same name, which led to neither matching all thecorrect values (with more than 100 mistakes in one, and several thousandin the other). The Perl extension has now been renamed to be Decomposition_Type=Noncanonical (short: dt=noncanon). It has the samemeaning as was previously intended, namely the union of all thenon-canonical Decomposition types, with Unicode Compat being just one ofthose. \p{Uppercase} and \p{Lowercase} have been brought into line with theUnicode definitions. This means they each match a few more charactersthan previously. \p{Cntrl} now matches the same characters as \p{Control}. This means itno longer will match Private Use (gc=co), Surrogates (gc=cs), nor Format(gc=cf) code points. The Format code points represent the biggestpossible problem. All but 36 of them are either officially deprecatedor strongly discouraged from being used. Of those 36, likely the mostwidely used are the soft hyphen (U+00AD), and BOM, ZWSP, ZWNJ, WJ, andsimilar, plus Bi-directional controls. \p{Alpha} now matches the same characters as \p{Alphabetic}. The Perldefinition included a number of things that aren't really alpha (allmarks), while omitting many that were. As a direct consequence, thedefinitions of \p{Alnum} and \p{Word} which depend on Alpha also change. \p{Word} also now doesn't match certain characters it wasn't supposedto, such as fractions. \p{Print} no longer matches the line control characters: Tab, LF, CR,FF, VT, and NEL. This brings it in line with the documentation. \p{Decomposition_Type=Canonical} now includes the Hangul syllables. The Numeric type property has been extended to include the Unihancharacters. There is a new Perl extension, the 'Present_In', or simply 'In',property. This is an extension of the Unicode Age property, but \p{In=5.0} matches any code point whose usage has been determined as of Unicode version 5.0. The \p{Age=5.0} only matches code pointsadded in precisely version 5.0. A number of properties did not have the correct values for unassignedcode points. This is now fixed. The affected properties areBidi_Class, East_Asian_Width, Joining_Type, Decomposition_Type, Hangul_Syllable_Type, Numeric_Type, and Line_Break. The Default_Ignorable_Code_Point, ID_Continue, and ID_Start propertieshave been updated to their current Unicode definitions. Certain properties that are supposed to be Unicode internal-only wereerroneously exposed by previous Perls. Use of these in regularexpressions will now generate, if enabled, a deprecated warning message.The properties are: Other_Alphabetic, Other_Default_Ignorable_Code_Point, Other_Grapheme_Extend, Other_ID_Continue, Other_ID_Start, Other_Lowercase,Other_Math, and Other_Uppercase. An installation can now fairly easily change which Unicode propertiesPerl understands. As mentioned above, certain properties are by defaultturned off. These include all the Unihan properties (which should beaccessible via the CPAN module Unicode::Unihan) and any deprecated orUnicode internal-only property that Perl has never exposed. The generated files in the lib/unicore/To directory are now moreclearly marked as being stable, directly usable by applications.New hash entries in them give the format of the normal entries,which allows for easier machine parsing. Perl can generate filesin this directory for any property, though most are suppressed. Aninstallation can choose to change which get written. Instructionsare in perluniprops. Regular Expressions U+0FFFF is now a legal character in regular expressions. http://perldoc.perl.org Page 2 Perl version 5.12.4 documentation - perl5113delta Modules and Pragmata Pragmata Changes constant Upgraded from version 1.19 to 1.20. diagnostics This pragma no longer suppresses Use of uninitialized value in range (or flip) warnings. [perl #71204] feature Upgraded from 1.13 to 1.14. Added the unicode_strings feature: use feature "unicode_strings"; This pragma turns on Unicode semantics for the case-changing operations(uc/lc/ucfirst/lcfirst) on strings that don't have the internal UTF-8 flag set,but that contain single-byte characters between 128 and 255. legacy The experimental legacy pragma, introduced in 5.11.2, has been removed,and its functionality replaced by the new feature pragma, use feature"unicode_strings". threads Upgraded from version 1.74 to 1.75. warnings Upgraded from 1.07 to 1.08. Added new warnings::fatal_enabled() function. Updated Modules Archive::Extract Upgraded from version 0.34 to 0.36. CPAN Upgraded from version 1.94_51 to 1.94_5301, which is 1.94_53 on CPANplus some local fixes for bleadperl. Includes better bzip2 support, improved FirstTime experience withauto-selection of CPAN mirrors, proper handling of modules removed from thePerl core, and an updated 'cpan' utility script CPANPLUS Upgraded from version 0.89_09 to 0.90. Encode Upgraded from version 2.38 to 2.39. ExtUtils::MakeMaker Upgraded from version 6.55_02 to 6.56. Adds new BUILD_REQUIRES key toindicate build-only prerequisites. Also adds support formingw64 and the new "package NAME VERSION" syntax. File::Path Upgraded from version 2.08 to 2.08_01. Module::Build Upgraded from version 0.35_09 to 0.36. Compared to 0.35, this version has anew http://perldoc.perl.org Page 3 Perl version 5.12.4 documentation - perl5113delta 'installdeps' action, supports the PERL_MB_OPT environment variable, adds a'share_dir' property for File::ShareDir support, support the "package NAMEVERSION" syntax and has many other enhancements and bug fixes. The'passthrough' style of Module::Build::Compat has been deprecated. Module::CoreList Upgraded from version 2.23 to 2.24. POSIX Upgraded from version 1.18 to 1.19. Error codes for getaddrinfo() and getnameinfo() are now available. Pod::Simple Upgraded from version 3.10 to 3.13. Safe Upgraded from version 2.19 to 2.20. Utility Changes perlbug No longer reports "Message sent" when it hasn't actually sent the message Changes to Existing Documentation The Pod specification (perlpodspec) has been updated to bring thespecification in line with modern usage already supported by most Pod systems.A parameter string may now follow the format name in a "begin/end" region.Links to URIs with a text description are now allowed. The usage of L< "section"> has been marked as deprecated. if.pm has been documented in "use" in perlfunc as a means to getconditional loading of modules despite the implicit BEGIN block around use. Installation and Configuration Improvements Testing improvements It's now possible to override PERL5OPT and friends in t/TEST Platform Specific Changes Win32